Habitat type and dispersal mode underlie the capacity for plant migration across an intermittent seaway.

Background and Aims: Investigating species distributions across geographic barriers is a commonly utilized method in biogeography to help understand the functional traits that allow plants to disperse successfully. Here the biogeographic pattern analysis approach is extended by using chloroplast DNA whole-genome 'mining' to examine the functional traits that have impacted the dispersal of widespread temperate forest species across an intermittent seaway, the 200 km wide Bass Strait of south-eastern Australia. Methods: Multiple, co-distributed species of both dry and wet forests were sampled from five regions on either side of the Strait to obtain insights into past dispersal of these biomes via seed. Using a next-generation sequencing-based pool-seq method, the sharing of single nucleotide polymorphisms (SNPs) was estimated between all five regions in the chloroplast genome. Key Results: A total of 3335 SNPs were detected in 20 species. SNP sharing patterns between regions provided evidence for significant seed-mediated gene flow across the study area, including across Bass Strait. A higher proportion of shared SNPs in dry forest species, especially those dispersed by birds, compared with wet forest species suggests that dry forest species have undergone greater seed-mediated gene flow across the study region during past climatic oscillations and sea level changes associated with the interglacial/glacial cycles. Conclusions: This finding is consistent with a greater propensity for long-distance dispersal for species of open habitats and proxy evidence that expansive areas of dry vegetation occurred during times of exposure of Bass Strait during glacials. Overall, this study provides novel genetic evidence that habitat type and its interaction with dispersal traits are major influences on dispersal of plants.

Genetic differentiation in spite of high gene flow in the dominant rainforest tree of southeastern Australia, Nothofagus cunninghamii.

Nothofagus cunninghamii is a long-lived, wind-pollinated tree species that dominates the cool temperate rainforests of southeastern Australia. The species' distribution is more or less continuous in western Tasmania but is fragmented elsewhere. However, it is unknown whether this fragmentation has affected the species' genetic architecture. Thus, we examined N. cunninghamii using 12 nuclear microsatellites and 633 individuals from 18 populations spanning the species' natural range. Typical of wind-pollinated trees, there was low range-wide genetic structure (FST=0.04) consistent with significant gene flow across most of the species' range. However, gene flow was not high enough to overcome the effects of drift across some disjunctions. Victorian populations (separated from Tasmania by the 240 km wide Bass Strait) formed a genetic group distinct from Tasmanian populations, had lower diversity (mean allelic richness (Ar)=5.4 in Victoria versus 6.9 in Tasmania) and were significantly more differentiated from one another than those in Tasmania (FST=0.045 in Victoria versus 0.012 in Tasmania). Evidence for bottlenecking was found in small populations that were at least 20 km from other populations. Interestingly, we found little divergence in microsatellite markers between the extremes of genetically based morphological and physiological altitudinal clines suggesting adaptive differentiation is strongly driven by selection because it is likely to be occurring in the presence of gene flow. Even though the cool temperate rainforests of Australia are highly relictual, the species is relatively robust to population fragmentation due to high levels of genetic diversity and gene flow, especially in Tasmania.

Diabetes UK evidence-based nutrition guidelines for the prevention and management of diabetes.

This article summarizes the Diabetes UK evidence-based guidelines for the prevention of Type 2 diabetes and nutritional management of diabetes. It describes the development of the recommendations and highlights the key changes from previous guidelines. The nutrition guidelines include a series of recommendations for the prevention of Type 2 diabetes, nutritional management of Type 1 and Type 2 diabetes, weight management, management of microvascular and macrovascular disease, hypoglycaemia management, and additional considerations such as nutrition support, end-of-life care, disorders of the pancreas, care of the older person with diabetes, nutrition provided by external agencies and fasting. The evidence-based recommendations were graded using the Scottish Intercollegiate Guidelines Network methodology and, in a small number of topic areas, where strong evidence was lacking, the recommendations were reached by consensus. The Diabetes UK 2011 guidelines place an emphasis on carbohydrate management and a more flexible approach to weight loss, unlike previous guidelines which were expressed in terms of recommendations for individual nutrient intakes. Additionally, the guidelines for alcohol have been aligned to national recommendations. The full evidence-based nutrition guidelines for the prevention and management of diabetes are available from: http://www.diabetes.org.uk/nutrition-guidelines.

Chloroplast evidence for geographic stasis of the Australian bird-dispersed shrub Tasmannia lanceolata (Winteraceae).

Few chloroplast-based genetic studies have been undertaken for plants of mesic temperate forests in the southern hemisphere and fossil-based models have provided evidence of vegetation history only at the broadest scales in this region. This study investigates the chloroplast DNA phylogeography of Tasmannia lanceolata (Winteraceae), a fleshy-fruited, bird-dispersed shrub that is widespread in the mountains of southeastern Australia and Tasmania. Thirty haplotypes were identified after sequencing 3206 bp of chloroplast DNA in each of 244 individuals collected across the species' range. These haplotypes showed unexpectedly strong phylogeographic structuring, including a phylogeographic break within a continuous part of the species' range, with the distribution of four major clades mostly not overlapping, and geographic structuring of haplotypes within these clades. This strong geographic patterning of chloroplast DNA provided evidence for the survival of T. lanceolata in multiple putative wet forest refugia as well as evidence for additional wet forest species refugia in southeastern Australia. In western Tasmania lower haplotype diversity below the LGM tree line compared to above the LGM tree line suggests that glacial refugia at high altitudes may have been important for T. lanceolata. The level of geographic structuring in T. lanceolata is similar to gravity dispersed southern hemisphere plants such as Nothofagus and Eucalyptus. Behavioural traits of the birds transporting seed may have had a strong bearing on the limited transport of T. lanceolata seed, although factors limiting establishment, possibly including selection, may also have been important.

Gas-phase production and photoelectron spectroscopy of the smallest fullerene, C20

Fullerenes are graphitic cage structures incorporating exactly twelve pentagons. The smallest possible fullerene is thus C20, which consists solely of pentagons. But the extreme curvature and reactivity of this structure have led to doubts about its existence and stability. Although theoretical calculations have identified, besides this cage, a bowl and a monocyclic ring isomer as low-energy members of the C20 cluster family, only ring isomers of C20 have been observed so far. Here we show that the cage-structured fullerene C20 can be produced from its perhydrogenated form (dodecahedrane C20H20) by replacing the hydrogen atoms with relatively weakly bound bromine atoms, followed by gas-phase debromination. For comparison we have also produced the bowl isomer of C20 using the same procedure. We characterize the generated C20 clusters using mass-selective anion photoelectron spectroscopy; the observed electron affinities and vibrational structures of these two C20 isomers differ significantly from each other, as well as from those of the known monocyclic isomer. We expect that these unique C20 species will serve as a benchmark test for further theoretical studies.

Computer-based neuropsychological screening for AIDS dementia complex.

OBJECTIVE: To test the efficacy of reaction time (RT) measures as a screening test for AIDS dementia complex (ADC). DESIGN AND METHODS: Forty-two patients with mild-to-moderate ADC and 33 healthy HIV-1-seronegative control subjects took a computer-administered battery of four RT measures: simple RT, choice RT, and two types of sequential RT (1 and 2). RESULTS: The performance of the ADC group was significantly worse than that of the control group on all four RT measures, but not all tasks were equally sensitive. The two tests of sequential RT were found to be the best discriminators, and receiver operating characteristic curves analyses indicated that the optimal cut-off z score was 1.0 for both tests. CONCLUSIONS: These preliminary results suggest that computer-based RT, using these two measures of sequential RT, may provide a sensitive method of detecting HIV-1-associated cognitive deficits.

Evaluation of autoantibodies to brain proteins in patients with AIDS dementia complex.

A high frequency of autoantibodies to brain proteins has been reported in HIV-1-positive patients. However, the specificity of this response has not been characterized. Using homogenized tissue from three normal brains, the presence of autoantibodies to human brain proteins was analyzed in 16 HIV-1-positive patients with AIDS dementia complex (ADC), 10 HIV-1-positive patients without ADC, 10 patients with multiple sclerosis, 10 patients with juvenile rheumatoid arthritis, and 10 normal controls. Although antibodies to various brain proteins were detected in sera from one-third HIV-1-infected individuals with or without ADC, the proteins recognized were different among different brains. Only one ADC patient had consistent seroreactivity to a 50-kDa brain-specific protein. Our results indicate that autoantibodies to brain proteins are infrequently present in patients with ADC.

Brain choline-containing compounds are elevated in HIV-positive patients before the onset of AIDS dementia complex: A proton magnetic resonance spectroscopic study.

The CNS is frequently involved in human immunodeficiency virus (HIV) infection. In recent studies using proton magnetic resonance spectroscopy, investigators found a significant reduction in N-acetyl aspartate, a metabolic marker of neurons, in late stages of dementia. To further understand the relationship between proton magnetic resonance spectroscopy changes and clinical disease and dementia, we compared 20 HIV-infected patients presenting at varying stages of acquired immunodeficiency syndrome (AIDS) dementia complex and infection to 10 age-matched controls. We found a significant reduction in N-acetyl aspartate/creatine only in patients who had advanced dementia and CD4 counts less that 200/microliter. By contrast, a significant elevation in compounds containing choline was present in patients in the early stages of HIV infection of who had CD4 counts greater than 200/microliter, in patients with normal MRI scans, and in all AIDS dementia complex groups, including subjects with no or minimal cognitive impairment. An elevated choline level also occurred in later stages of HIV infection (CD4 < 200/microliter). Our results suggest that an increase in choline occurs before N-acetyl aspartate decrements, MRI abnormalities, and the onset of dementia, and may therefore provide a useful marker for early detection of brain injury associated with HIV infection.

A comparison of brain perfusion SPECT in cocaine abuse and AIDS dementia complex.

Intravenous drug use is a major risk factor for HIV-1 infection. Since both AIDS dementia complex (ADC) and cocaine have been associated with abnormal brain perfusion imaging, we compared the scintigraphic patterns of ADC patients and cocaine polydrug users with normal control subjects using 99mTc-HMPAO SPECT. We found a high incidence of cortical defects in both ADC (100%) and cocaine-dependent (90%) subjects. In the cocaine and ADC patients, cortical defects were most frequent in the frontal, temporal and parietal lobes and occurred with similar frequency in the two populations. In both groups, the number of cortical defects per subject was higher than normal subjects (10.0 +/- 5.0 for ADC, 10.1 +/- 5.2 for cocaine and 0.7 +/- 1.5 for normal), background activity was high (a 65% and 60% incidence for ADC and cocaine, respectively), and basal ganglia involvement was frequent (40% and 65% for ADC and cocaine). We conclude that the brain perfusion pattern, while a sensitive indicator of ADC, cannot be distinguished from chronic cocaine polydrug use and caution should therefore be applied before entertaining a specific diagnosis.

EEG abnormalities in patients with atypical panic attacks.

BACKGROUND: Panic attacks and certain partial seizures have phenomenologic similarities which suggest that they may somehow be related. No evidence of such a relationship, however, was found when the routine EEGs of patients with panic attacks were examined. METHOD: Fifteen subjects with atypical panic attacks who met DSM-III-R criteria for panic disorder agreed to have routine followed by prolonged ambulatory EEG monitoring with sphenoidal electrodes. Fourteen subjects actually underwent monitoring; 1 had a panic attack during premonitoring routine EEG. RESULTS: Focal paroxysmal EEG changes consistent with partial seizure activity occurred during panic attacks in 33% (N = 5) of the 15 subjects; 2 (40%) of the 5 subjects with panic-related EEG changes had normal routine EEGs. Multiple attacks were recorded before panic-related EEG changes were demonstrated in several subjects. CONCLUSION: It may be necessary to monitor the EEG during multiple panic attacks to reveal an association between atypical panic attacks and epileptiform EEG changes.

Two strategies to increase adherence to HIV antiretroviral medication: life-steps and medication monitoring.

Advances in the medical treatment of HIV have made it clear that adherence to highly active antiretroviral treatment is a crucial feature for treatment success. The present paper had two goals: (1) to examine psychosocial predictors of adherence in persons receiving HIV antiretroviral therapy; (2) to compared two minimal-treatment interventions to increase HIV medication adherence in a subset of persons who self-reported less than perfect adherence. One of the interventions, Life-Steps, is a single-session intervention utilizing cognitive-behavioral, motivational interviewing, and problem-solving techniques. The other intervention, self-monitoring, utilizes a pill-diary and an adherence questionnaire alone. Significant correlates of adherence included depression, social support, adherence self-efficacy, and punishment beliefs about HIV. Depression was a significant unique predictor of adherence over and above the other variables. Both interventions yielded improvement in adherence from baseline, and the Life-Steps intervention showed faster improvements in adherence for persons with extant adherence problems.

Neonatal sensitization to latex.

Babies born in delivery rooms of hospitals are exposed to latex through skin and mucous membrane contact with prepowdered latex gloves worn by midwives and doctors, and through the inhalation of latex-bound starch powder in the air of the delivery room. This paper examines the hypothesis that they are at risk for latex sensitization, and that part of the sharp increase of childhood asthma, eczema and anaphylaxis in the past 30-40 years may be linked. These possibilities seem hitherto unsuspected. In over 700 papers on latex allergy no mention of neonatal exposure to latex has been found. Even obstetric papers discussing the risks for an atopic mother (atopy - a tendency to develop allergies) do not seem to anticipate any risk for the baby, who might also be atopic. Latex allergy is primarily regarded as an occupational hazard. This paper suggests that it is a hazard for every baby handled by latex gloves at birth.

Overcoming families' fears and concerns in the donation discussion.

Research into the fears and concerns families have about donation and other issues at the time of the donation discussion substantiates that many fears and concerns act as impediments to consent. Twenty fears and concerns voiced by families at the time of the donation discussion have been identified. Specific strategies have been developed to deal with 19 of those concerns. Using gentle probing questions and targeted strategies, trained requestors may successfully address many fears and concerns, thus increasing the likelihood of the family consenting to donation.

Fears and concerns expressed by families in the donation discussion.

Previous research has identified specific fears and concerns among the general public about organ and tissue donation. However, little to none of that research has dealt with fears and concerns at the time of the donation discussion. In this study, 180 experienced coordinators ranked the fears and concerns most commonly heard during the donation discussion. They further classified the fears and concerns according to the ease with which they can be addressed. Subsequently, the fears and concerns were classified in 4 groups: often heard and easy to deal with, often heard and hard to deal with, seldom heard and easy to deal with, seldom heard and hard to deal with. The results can be used to stimulate further research on family fears and concerns, to train and retrain coordinators to address those concerns in the donation discussion, and to improve existing strategies for increasing organ and tissue donation.

Transmigration of permanent mandibular canines.

Transmigration is a rare occurrence relating to the movement of a mandibular canine across the mid-line of the mandible. Two cases are presented where patients referred for assessment of third molar problems subsequently revealed on radiological examination the asymptomatic phenomenon of transmigration. With dental panoramic radiography becoming more widespread among dental practitioners it is possible that more cases of transmigration will be observed.

Neonatal sensitisation to latex: a hypothesis.

The exposure of babies to latex gloves at birth may be behind the dramatic increase in childhood allergies in the past 40 years. Jennifer Worth explores this theory and calls for a ban on the use of pre-powdered latex gloves in maternity units.